Generally, container cargo, commercially traded in international imports and exports, is placed, together with the container, on a carriage called a container chassis in the domestic distribution network. The container chassis is towed and transported by a towing vehicle such as a tractor, railroad engine or the like capable of towing the container chassis.
Incidentally, such container cargo is generally transported without having checked its condition of loading in the container and, as a result, various inconveniences caused by container transport vehicles have been heretofore viewed as social issues. For example, situations resulting from the biased loading of cargo in the container (e.g., cargo pile collapse/cargo falling occurring when the container door is opened and unstable travel motions of the container transport vehicle when travelling along a curved road section) are becoming social problems.
On the other hand, various technologies for measuring the condition of loading of the cargo in a vehicle such as four-wheeled truck and various coping techniques for the abnormal loading of cargo have been proposed.
For example, there is proposed a conventional technique which is directed to a braking method for a trailer (which corresponds to the container chassis) having a computerized braking system (brake control system) (see JP-A-2005-313879). In accordance with this conventional technology, vehicle rollover on a narrow curved road section or at an automobile expressway exit may be prevented.
In addition, there is proposed another conventional technique in which the rolling frequency of a truck is measured, thereby to derive the inertia moment in the front/rear longitudinal direction (travel direction), mass, and inclination of the vehicle (see JP-A-2000-28427). In accordance with this conventional technology, the inertia moment, mass, and inclination of the vehicle can be calculated unambiguously and, for example, the possibility of vehicle rollover is predictable in advance.
In addition, there is still another conventional technique that is proposed with a view to preventing the occurrence of rollover of an articulate type dump truck due to the inclination thereof caused by biased loading when the dump body is raised in order to discharge laden earth/sand or the like during stop (see JP-A-2000-302063).
In addition, there is proposed yet another conventional technique in which the weight of cargo loaded on a load deck of a truck is found using pressure-sensitive sensors which are so arranged as to cover the surface of the load deck and the static distribution of load of the truck load deck is found in two-dimensional plane (see JP-A-H05-213108). In accordance with this conventional technology, abnormal loading, such as partial laden weight excess or laden weight imbalance in the truck, is digitally, objectively detected, thereby preventing the occurrence of cargo pile collapse and vehicle rollover.
In addition, there is proposed still yet another conventional technique in which an attitude control system is provided under the load deck of a truck to sense centrifugal force produced when the truck goes around a curved road section and the attitude control system of the load deck is operated to automatically tilt the load deck thereby to overcome the centrifugal force (see JP-A-H05-124543).
Finally, there is proposed yet still another conventional technique in which the distribution of load and the inclination, in horizontal planes in the front/rear and left/right directions, of the load deck or the lateral acceleration during travel along a curved road section is measured, thereby to derive the location of the center of gravity, in the vertical direction, of the cargo loaded on the truck load deck (see JP-A-2001-97072). In accordance with this conventional technology, a specific vehicle, whose load deck is loaded with cargo in a specific condition of loading, was previously subjected to test runs over some different road surfaces (e.g., a straight track, curved track and so on), and values for inclination and lateral acceleration obtained by the test runs were measured to create a matrix database of the locations of the centers of gravity in the vertical direction according to the conditions of loading of the cargo and the differences in road surface condition. Consequently, if such a database is carried in the actual operation of a vehicle, this will make it possible to estimate the location of the center of gravity in the vertical direction by entry of load distribution and inclination values into the matrix database depending upon the condition of loading of the cargo.